Bone mineral density and intervertebral disc height in type 2 diabetes

Abstract

Background Studies of the effect of type 2 diabetes (T2D) on bone mineral density (BMD have produced conflicting results, possibly due to failure to adjust for potential confounding factors. Nonetheless, T2D has consistently been associated with increased fracture risk, suggesting that other factors might play a role. Objective This study assesses the relationship between T2D and BMD at the femoral neck and spine in diabetic and non-diabetic subjects, after adjusting for multiple covariates which may affect BMD. Intervertebral disc height was also investigated in view of its possible relation to fracture risk. Methods A cross-sectional study of 100 patients with T2DM of at least 5 years duration and 86 non-diabetic subjects was carried out. Results There were no significant differences in T scores in either the spine or femoral neck after adjustment for potential confounding variables between T2D subjects and controls. Diabetic patients had a statistically lower intervertebral disc height between the 2nd and 3rd lumbar vertebrae (D3) after adjustment for potential confounders (p = 0.004). Urinary albumin:creatinine ratio, total cholesterol, LDL-cholesterol and cigarette smoking were independently associated with lower height of D3 in diabetic subjects. Conclusions There is no significant independent association between T2D and BMD. However we found a novel association of significantly lower disc height in patients with T2D. This may contribute to the increased vertebral fracture risk in subjects with T2D. Further studies are needed to investigate the relationship of disc height, T2D and fracture risk.